title: The role of MRS in the differentiation of benign and malignant soft tissue and bone tumors.
abstract: OBJECTIVE
  The aim of our study was to investigate the value of choline in the discrimination of benign and malignant soft tissue and bone tumors.
  
  
  METHODS
  The study group consisted of thirty subjects with bone or soft tissue tumors larger than 1.5 cm in diameter. The experiments were performed in a 1.5T MR scanner. Coils were selected according to specific locations. A single-voxel MRS was performed for three different TE (time to echo) (31, 136, 272 ms). The volume of interest was positioned on the brightest enhancement. The presence of a cholin peak on at least 2 of these spectrums was considered as the marker of malignancy. The sensitivity, specificity and accuracy of the MRS in the detection and diagnosis of malignant lesions were calculated. The reproducibility of MRS and histopathological results were tested with kappa statistics.
  
  
  RESULTS
  Histopathologically, 18 (60%) of the lesions were classed as malignant whereas 12 (40%) were classed as benign. With MRS, 15 (50%) of these lesions were classed as malignant and 15 (50%) as benign. Two patients who were found spectroscopically to have malignant tumors were shown histopathologically to have benign types. Five patients with an MRS showing a benign type were classed with malignant types in histopathological examinations. MRS had a sensitivity rate of 72.2%, specificity of 83.3%, and an accuracy rate of 76.6% in detecting malignant bone and soft tissue tumors. The interrater reliability of both techniques had a kappa value of 0.533.
  
  
  CONCLUSIONS
  MRS may help in the differentiation of benign and malignant soft tissue and bone tumors.
authors.affiliation: Erciyes University, Faculty of Medicine, Department of Radiology, Kayseri, Turkey. selimdoganay@gmail.com
authors.forename: Selim
authors.initials: S
authors.lastname: Doganay
authors.forename: Tayfun
authors.initials: T
authors.lastname: Altinok
authors.forename: Alpay
authors.initials: A
authors.lastname: Alkan
authors.forename: Bayram
authors.initials: B
authors.lastname: Kahraman
authors.forename: Hakki Muammer
authors.initials: HM
authors.lastname: Karakas
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001859:Bone Neoplasms / Q000378:metabolism / Q000473:pathology*; D002794:Choline / Q000378:metabolism*; D003287:Contrast Media; D003937:Diagnosis, Differential; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012983:Soft Tissue Neoplasms / Q000378:metabolism / Q000473:pathology*
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA; D002794:Choline